Three-dimensional integrated circuits are employed in applications in which space is a critical design factor. As the demand for more functionality in less space increases, so does the demand for three-dimensional packaging. In addition to the benefit of reducing space, these designs may also realize higher speeds because interconnects between circuit components may be shorter.
When integrated circuits are stacked, there needs to be a way to supply power, ground, and input/output (I/O) signals to each integrated circuit in the stack. Further, there needs to be a way to connect each integrated circuit in the stack to the next level of interconnection (e.g., to the next integrated circuit or to a printed circuit board). Additionally, there needs to be a way to dissipate heat generated by the stacked integrated circuits.
A method for stacking integrated circuits of the same size is important in some applications. For example, stacking memory chips to form a memory module is commonly performed to increase data storage capacity in an electronic device. Accordingly, there needs to be a way of stacking integrated circuits having the same size.